1. Field of the Invention
The present invention relates to a network, work station, personal computer system or similar image forming system including a plurality of host computers. More particularly, the present invention is concerned with an image forming system wherein an optional mail box, or paper outputting means for personal management, is connected to an image forming apparatus.
2. Discussion of the Background
An image forming system of the kind described has recently been put on the market and has an optional mail box connected to an image forming apparatus. The mail box has personal paper outputting devices and a general or shared paper outputting device in order to allow various kind of information to be interchanged. Japanese Patent Laid-Open Publication No. 2-186429, for example, proposes a network type printing system shared by a plurality of computers and having a plurality of trays for receiving printings. In this system, some of the trays are each provided with a key lock and are unlocked by an ID code received from a particular host, thereby ensuring the secrecy of printings or documents. Japanese Patent Laid-Open Publication No. 4-48323 teaches an image forming system capable of protecting private data printed out by a printer from a third party. This system has means for determining whether or not the printed data are meant for a particular user, paper outputting means for outputting personal printings and general printings separately on the basis of the result of decision, and a stacker for receiving the personal printings. Only if a password entered is identical with a password assigned to the user, the stacker allows the private printings to be taken out.
The conventional image forming systems described above guarantee the secrecy of documents. However, because the mail box of the system is often used as a private spot for outputting printings, any trouble occurring in processings dealing with a single user prevents printing meant for other users from being started.